Changing a keyword test URL for multiple tests.

In general it's not a good idea to hard code anything environment related directly into your tests. A project variable and / or a config file you read into set it would be your best option. A project variable can also be used as the url property of your name mapping criteria.

That said in a pinch, keyword tests files are just xml files, so you should be able to a search and replace in them using any text editor or a powershell script.